title: Comparative susceptibility of different biological forms of Anopheles stephensi to Plasmodium berghei ANKA strain.
abstract: BACKGROUND
  There are varying degrees of compatibility between malaria parasite-mosquito species, and understanding this compatibility may be crucial for developing effective transmission-blocking vaccines. This study investigates the compatibility of different biological forms of a malaria vector, Anopheles stephensi, to Plasmodium berghei ANKA strain.
  
  
  METHODS
  Several biologically different and allopatric forms of A. stephensi were studied. Three forms were isolated from different regions of southern Iran: the variety mysorensis, the intermediate form and the native type form, and an additional type form originated from India (Beech strain).The mosquitoes were experimentally infected with P. berghei to compare their susceptibility to parasitism. Anti-mosquito midgut antiserum was then raised in BALB/cs mice immunized against gut antigens from the most susceptible form of A. stephensi (Beech strain), and the efficacy of the antiserum was assessed in transmission-blocking assays conducted on the least susceptible mosquito biological form.
  
  
  RESULTS
  The susceptibility of different biological forms of A. stephensi mosquito to P. berghei was specifically inter-type varied. The Beech strain and the intermediate form were both highly susceptible to infection, with higher oocyst and sporozoite infection rates than intermediate and mysorensis forms. The oocyst infection, and particularly sporozite infection, was lowest in the mysorensis strain. Antiserum raised against midgut proteins of the Indian Beech type form blocked infection in this mosquito population, but it was ineffective at blocking both oocyst and sporozoite development in the permissive but geographically distant intermediate form mosquitoes. This suggests that a strong degree of incompatibility exists between the mosquito strains in terms of midgut protein(s) acting as putative ookinete receptors.
  
  
  CONCLUSIONS
  The incompatibility in the midgut protein profiles between two biological forms of A. stephensi demonstrates a well-differentiated population structure according to geographical origin. Therefore, the design of potential transmission-blocking strategies should incorporate a more thorough understanding of intra-species variations in host-parasite interactions.
authors.affiliation: Department of Medical Entomology and Vector Control, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hamid R
authors.initials: HR
authors.lastname: Basseri
authors.forename: Habib
authors.initials: H
authors.lastname: Mohamadzadeh Hajipirloo
authors.forename: Mulood
authors.initials: M
authors.lastname: Mohammadi Bavani
authors.forename: Miranda M A
authors.initials: MM
authors.lastname: Whitten
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000852:Anopheles / Q000469:parasitology*; D018562:Disease Transmission, Infectious; D004797:Enzyme-Linked Immunosorbent Assay; D006790:Host-Parasite Interactions; D007106:Immune Sera; D007492:Iran; D051379:Mice; D008807:Mice, Inbred BALB C; D010962:Plasmodium berghei / Q000235:genetics*; D013045:Species Specificity; D018709:Statistics, Nonparametric
chemical_list: D007106:Immune Sera